This application relates to the field of wireless communications equipment, and more particularly, data terminal apparatuses for bridging circuit switched and packet switched networks.
Monitoring the residential, commercial, and industrial complexes of buildings throughout the United States are a variety of user equipment. Examples of such user equipment include meter reading devices which measure consumption of various utility commodities such as natural gas, electricity and water via an electrical or electro-mechanical transducer. The meter reading devices are typically analog devices that record either a first reading and a second reading of the measured commodity over a period of time, or, alternatively, a cycling total (that is, a running total that recycles after a certain number is reached).
Generally, service personnel for the utility provider physically appear at or near the meter reading device to record consumption of the commodity each month. The recorded consumption from the meter reading device is then fed into a database used for billing purposes which in turn generates an invoice for the consumer based on user""s consumption of the measured commodity.
In urban areas, the number of meter reading devices that need to be recorded is tremendous. Although the overhead associated with sending service personal to a desired location can be amortized by consolidation of meter reading devices at a particular location, for example, in a high-density residential development such as an apartment complex, the cost can still be significant. In rural areas, however, the cost is higher as meter reading cannot generally be amortized over a number of meter reading devices read at a single location.
Various techniques are employed by utility companies to reduce the cost of sending service personal to a physical site.
For example, a simple method is the use of stochastic techniques for extrapolating a measured quantity for a current reading from one or more past values or a moving or seasonal average. This technique is designed to reduce the frequency of meter reading. A disadvantage, however, is the fact that the extrapolated reading can be greatly under or over the actual consumption, such as the case where a consumer is simply not present and no services are used, or when an unusual weather pattern occurs and consumption is significantly increased.
Another technique is the use of radio-based meter reading devices. For example, each meter reading device includes a radio, the radio capable of broadcasting a meter reading to a nearby receiver. In the Middle East for example, such a system is often employed because service personnel are frequently denied access to a property when the property owner (a man) is not home. The radio based meter reading devices allow service personnel to drive near the radio meter reading device with a receiver device to read the meter. With such technology service personnel do not need to enter the property. An advantage of such a system is that, in rural areas, the time it takes service personnel to read the meters can be reduced.
For example, one system might require service personnel to physically drive by or near a collection of meter reading devices in order to communicate with the devices. The data collected in the xe2x80x9cdrive-byxe2x80x9d would be later uploaded to a centralized data collection system.
Another solution might include periodic stations that collect wireless data from the devices. The periodic stations, in turn could include a land-line modem that communicates with the centralized data collection system by way of circuit switched calls. Such a solution offers an alternative to deploying service personnel, however, setting up phone lines to service the periodic stations can also be expensive. Moreover, circuit switched calls can also be expensive.
The problems mentioned above are exacerbated by deregulation of the utilities industry in the United States. It is now possible for several different suppliers of electricity to service a single metropolitan area. This, in turn, results in a non-contiguous patchwork of service areas that service personnel may have to monitor. No longer can it be assumed that all users in a particular geographic area receive electrical power from a single service provider. Indeed, on a single residential block every household may have a different service provider. Moreover, the alleged ease with which a consumer may switch service providers further complicates the circumstance. Accordingly, the ability to amortize the costs of collecting usage measurements is reduced.
A data terminal apparatus comprising a wireless radio and a communications bridge is provided. The data terminal apparatus provides a link between data from a user equipment and a GSM network, connecting user equipment designed for circuit switched call link communications to a destination equipment via short message service or general packet radio service communications. According to an aspect of the invention, the data terminal apparatus simulates a circuit switched call link to the user equipment, thereby bridging legacy serial data communications systems with convenient wireless network technology. In one embodiment, the invention is particularly advantageous in utility service monitoring applications.